The "Plasmid and Chromosome Dynamics" Gordon Conference will be held at Colby-Sawyer College, New London, New Hampshire, on August 1-6, 1999. The two dominant themes of the Conference will be replication and segregation with emphasis on mechanisms by which these processes are regulated in the cell cycle. This is an exciting time for the analysis of chromosome structure and maintenance functions, because many new ideas and technologies are being applied to solve long-standing and fundamental biological problems and to understand molecular bases of diseases. Defects in chromosome replication and segregation have been identified to be the cause of drug resistance to cancer chemotherapy, xeroderma pigmentosum, Cockayne's syndrome, trisomy-associated mental retardation and heart disease, human cancer and aging, to name a few. The conference provides a unique opportunity for scientists working on pro-karyotic and eukaryotic biological systems to interact and exchange ideas and data on chromosome and plasmid behavior. Other than being model replicons, bacterial plasmids are important in their own right as they often marry multiple drug resistance markers and virulence genes, have broad host range and continue to be one of the vital tools of molecular biology and biotechnology. The research laboratories participating in this conference work on parallel problems in chromosome biology, and it is increasingly apparent that the underlying mechanisms overlap. However, many of these researchers do not regularly attend the same specialized conferences and therefore do not have opportunities to interact. Since its inception in early 80's, the Conference has met every second year and played a central role in maintain communication and collaboration among the diverse group of scientists who find that an understanding of chromosome structure, function and maintenance is critical to their work. The meeting will have about 120 participants, most of whom are principal investigators in academic institutions from throughout the world the world. In addition, postdoctoral fellows, graduate students, and members of industrial laboratories will attend. There will be 45 lectures that will cover model organisms as well as humans and a range of approaches including genetics, cell biology, biochemistry, molecular and structural biology. All registrants not speaking will be encouraged to present posters. Based on the success of this meeting in former years, we anticipate that unique and productive ideas will result from the interchanges at this meeting.